Adverse effect of unspecified psychodysleptics, sequela

This code signifies a long-term or residual effect resulting from an adverse reaction to an unspecified hallucinogenic substance. These sequelae are persistent conditions that arise after the acute phase of the adverse drug event has passed. Examples include chronic psychosis, persistent perceptual disturbances, or other lasting neurological or psychological impairments.

Use this code when documenting a patient presenting with a chronic or residual condition directly attributable to a past adverse effect from an unknown hallucinogen. This applies when the original adverse event is no longer active, but its lasting consequences are being treated or evaluated. It is crucial that the specific hallucinogen involved in the initial adverse reaction is not identified.

• Always assign this code as a secondary diagnosis, following the code for the specific sequela being treated.
• Ensure documentation clearly links the current condition to a past adverse effect of an unspecified hallucinogen.
• Verify that the "S" seventh character for sequela is appropriate, indicating a late effect of the adverse event.